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Adición de conjugado reductor catalizado por níquel a las enonas a través de intermediarios de allilníquel

Ruja Shrestha¹, Stephanie C M Dorn, Daniel J Weix

¹Department of Chemistry, University of Rochester, Rochester, New York 14627-0216, USA.

Journal of the American Chemical Society

|December 29, 2012

Resumen

Una nueva reacción catalizada por níquel permite la síntesis de éteres de enol silílico utilizando haloarenos y cetonas o aldehídos α,β-insaturados. Este método ofrece una alternativa versátil para crear moléculas orgánicas complejas.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis es la catálisis.
Metodología sintética de la metodología sintética.

Sus antecedentes:

La síntesis tradicional de éteres de sililenoles β-disubstituidos a menudo implica la adición de conjugado catalizado por cobre y la silición de enolato.
Existen limitaciones en el alcance del sustrato y los requisitos de reactivo para los métodos existentes.

Objetivo del estudio:

Desarrollar una vía sintética alternativa y eficiente para los éteres de sililenoles β-disubstituidos.
Para utilizar haloarenas como socios de acoplamiento, evitando la necesidad de reactivos nucleófilos de arilo.

Principales métodos:

Una reacción de acoplamiento catalizada por níquel entre cetonas/aldehídos α,β insaturados y haluros orgánicos.
Empleando neocuproína o bipiridina como ligandos para el catalizador de níquel.
Utilizando trialkylchlorosilane como un agente de silación.

Principales resultados:

Síntesis exitosa de éteres de sililenoles β-disubstituidos mediante el uso de haloarenos.
Tolerancia demostrada a diversos grupos funcionales, incluidos los aldehídos, las cetonas, los nitriles y las sulfonas.
Confirmó la primera adición de conjugado reductor catalítico de haluros orgánicos a través de un intermediario de allilniquel.

Conclusiones:

El método desarrollado catalizado por níquel proporciona un enfoque robusto y versátil para la síntesis de éteres de sililenoles.
La selectividad de la reacción se rige por la reactividad del catalizador y los efectos estéricos del ligando, minimizando las reacciones secundarias.
Esta metodología amplía el conjunto de herramientas para la construcción de moléculas orgánicas complejas.

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